Abstract: This study is to develop a method to assay the biologic activity of anti-TNF-α(tumor necrosis factor-alpha)monoclonal antibodies. TNF-α stimulates the expression of adhesion molecules E-Selectin(ELAM-1)in human umbilical vein endothelial cells(HUVEC), whereas anti-TNF-αantibodies suppress the expression of ELAM-1 in HUVEC cells through neutralizing TNF-α. Based on this principle, we developed and validated a method for the bioactivity assay of the antibodies. The result showed that the assay method was established successfully, and the specificity of the method was validated to be feasible. The recovery rate was 92.1%-102.1%, and the RSD was ≦ 7.66% while repeated 12 times. The linear range in 50% to 150% was fine, and the correlation coefficient was 0.99. Conclusively, this method is well suited as an activity assay of antibodies in vitro.

Key words: monoclonal antibody, HUVEC cell, ELAM-1, TNF-α